Osteoarthritis 'could be re-categorised as two distinct groups of disease'

Published on 17 January 2018

Osteoarthritis could be treated more effectively in the future by dividing patients into two distinct disease groups, according to new research.

The Arthritis Research UK-funded study, carried out by the University of Manchester, has discovered that the current definition of osteoarthritis may actually encompass two separate groups with different disease activity patterns, and that developing new treatments for both versions may be more effective than the current one-size-fits-all approach.

Two different patterns of disease activity

Published in the Annals of the Rheumatic Diseases, the research involved a mathematical analysis of thousands of genes expressed in the cartilage of 60 individual patients with knee osteoarthritis, with samples separated into categories based on the level of active metabolism in the diseased tissue.

Key genetic differences were found between the two groups of patients that emerged, with a list of biomarkers also developed that could be used to help distinguish between them by analysing the synovial fluid, which is found in the cavities of joints.

It is thought that the variations between these two categories could be used to predict different responses to treatment, and may explain why treating osteoarthritis as a single condition has proven unproductive.

Potential implications

Researchers hope this finding will pave the way for future research into new drugs and treatments that are targeted to each group, making it easier to design effective drug trials and determine which patients would be most likely to respond to treatment.

Professor Tim Hardingham, of the University of Manchester's Wellcome Trust Centre for Cell-Matrix Research and Division of Cell Matrix Biology and Regenerative Medicine, said: "This is a significant step forward in our understanding of osteoarthritis, a complex and debilitating disease which has a major socioeconomic impact.

"However, the discovery is just the first step in a long process that may lead to developing new drugs and treatments that are targeted to each group."

Arthritis Research UK's view

Dr Devi Sagar, research liaison manager at Arthritis Research UK, said: "We know that millions of people live with the daily pain of osteoarthritis. This, coupled with stiffness and fatigue, can make everyday life difficult, limiting a person's ability to get dressed, go to work or even climb the stairs.

"Although it's still very early days, this study is good news for people with osteoarthritis and helps us to build on our understanding of the condition. We have known for some time that osteoarthritis is something of an umbrella term, with people having similar symptoms, but different responses to treatments. We welcome more research, like this study, that may eventually pave the way to better diagnosis and more targeted treatments for osteoarthritis, so that people with arthritis can live the pain-free life they deserve."

For more information, go to www.arthritisresearchuk.org.Arthritis Research UK fund research into the cause, treatment and cure of arthritis. You can support Arthritis Research UK by volunteering, donating or visiting our shops.